1. Field of the Invention
The present invention relates to an apparatus for characterizing particles suspended in a liquid, especially a self-contained disposable cartridge for single-use analysis, such as for single-use analysis of a small quantity of whole blood.
2. Description of the Background Art
Present instruments for particle characterization such as counting and sizing are fairly expensive, immobile and require operation by trained personnel. The consequence hereof has been that many instruments are placed in dedicated laboratories that are operated by specialized personnel. Furthermore, the samples to be analyzed must be transported to this laboratory and the results are reported back to the requiree.
However, efforts have been made to provide a disposable cartridge for particle characterization. WO 03/104772 discloses a cartridge for analysis of a blood sample. The cartridge disclosed in WO 03/104772 can be used for determination of the content of haemoglobin and for counting and differentiation between three types of white blood cells (WBCs). In one embodiment the platelets are counted after lysing of the blood sample. In another embodiment the cartridge comprises two orifices and two mixing chambers for characterization of a blood sample. The blood sample is diluted in a first mixing chamber for particle characterization of WBCs through a first orifice and a part of the diluted sample is further diluted in a second mixing chamber for particle characterization of red blood cells (RBCs) and platelets (PLTs) through a second orifice.
WO 03/044488 discloses a disposable apparatus for use in blood testing, the apparatus being adapted for simultaneous dilution of blood into two different dilution ratios in two different mixing chambers.